Identification of candidate genes involved in anthocyanin accumulation using Illmuina-based RNA-seq in peach skin

Peach (Prunus persica) is one of the most economically important crops, its fruit quality is defined by various criteria, including external quality and fruit taste. Peach contain anthocyanins as the main pigment with important nutritional and medical usages. Therefore, increasing the anthocyanin content in peach skin can make the fruit appearance of bright and attractive. This study investigated the formation mechanism of the external quality of peach fruit and utilized RNA-seq technology to analyze the molecular mechanisms of anthocyanin biosynthesis regulation in P. persica fruit skin. Approximately 333,899,176 clean reads were obtained, 25,694 unigenes were annotated in five public databases. After the different expression genes of the compared sequences were quantitated by RPKM method and sifted by a limited term, in total, 1665, 3214, and 639 differentially expressed genes were screened among 120 DAF (days after flowering) vs 105 DAF, 135 DAF vs 105 DAF, and 135 DAF vs 120 DAF, respectively. We identified 15 structural genes, 16 transcription factors, and 17 transferase genes that may be involved in the anthocyanin biosynthesis from P. persica and analyzed their expression patterns by using real-time PCR. Our results presented comprehensive gene expression information about peach skin transcriptome; and enhanced our understanding of key genes regulating the biological pathways of anthocyanin biosynthesis. This study could help us understand the molecular mechanism of anthocyanin metabolism in peach skin and provide important technical support for regulating peach skin coloration.